docs: def setGroups(self, groups, kerningGroupConversionRenameMaps=None):
          """ Copy the groups into our font. """
          skipping = []
          for name, members in groups.items():
              checked = []
              for m in members:
                  if m in self.font:
                      checked.append(m)
                  else:
                      skipping.append(m)
              if checked:
                  self.font.groups[name] = checked
          if skipping:
              if self.verbose and self.logger:
                  self.logger.info("\tNote: some glyphnames were removed from groups: %s (unavailable in the font)", ", ".join(skipping))
          if kerningGroupConversionRenameMaps:
              # in case the sources were UFO2, 
              # and defcon upconverted them to UFO3
              # and now we have to down convert them again,
              # we don't want the UFO3 public prefixes in the group names
              self.font.kerningGroupConversionRenameMaps = kerningGroupConversionRenameMaps